On Thu, Jun 25, 2015 at 09:02:45PM +0000, bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=100491 > > Bug ID: 100491 > Summary: Oops under bitmap_start_sync [md_mod] at boot [...] > Reading all physical valumes. This may take a while... > Found volume group "rootvg" using metadata type lvm2 > device-mapper: raid: Device 0 specified for rebuild: Clearing superblock > md/raid1:mdX: active with 1 out of 2 mirrors > mdX: invalid bitmap file superblock: bad magic > md-cluster module not found. > mdX: Could not setup cluster service (256) > BUG: unable to handle kernel NULL pointer dereference at 0000000000000100 > IP: [<ffffffff8159e4a9>] _raw_spin_lock_irq+0x29/0x70 > PGD 0 > Oops: 0002 [#1] PREEMPT SMP [...] I'm marking this as a regression in bugzilla, since this seems to prevent booting on 4.1.0 at least in certain circumstances (namely those which I have; I wonder if any raid1 recovery works?) while 4.0.6 boots correctly. I bisected this down to one of four commits. Well, assuming that the problem was caused by changes in drivers/md; a fair assumption, I think. The commits are: $ git bisect view --oneline f9209a3 bitmap_create returns bitmap pointer 96ae923 Gather on-going resync information of other nodes 54519c5 Lock bitmap while joining the cluster b97e9257 Use separate bitmaps for each nodes in the cluster The crash happens whether or not CONFIG_MD_CLUSTER is enabled. Here's the versions I tested: git bisect start '--' 'drivers/md' # bad: [b953c0d234bc72e8489d3bf51a276c5c4ec85345] Linux 4.1 # good: [39a8804455fb23f09157341d3ba7db6d7ae6ee76] Linux 4.0 # bad: [9ffc8f7cb9647b13dfe4d1ad0d5e1427bb8b46d6] md/raid5: don't do chunk aligned read on degraded array. # bad: [6dc69c9c460b0cf05b5b3f323a8b944a2e52e76d] md: recover_bitmaps() can be static # bad: [4b26a08af92c0d9c0bce07612b56ff326112321a] Perform resync for cluster node failure # good: [cf921cc19cf7c1e99f730a2faa02d80817d684a2] Add node recovery callbacks # skip: [96ae923ab659e37dd5fc1e05ecbf654e2f94bcbe] Gather on-going resync information of other nodes # bad: [f9209a323547f054c7439a3bf67c45e64a054bdd] bitmap_create returns bitmap pointer # skip: [54519c5f4b398bcfe599f652b4ef4004d5fa63ff] Lock bitmap while joining the cluster Sami -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
